Help with molds, please

[lemming]

Gentlemen -

I cast 357 RN and SWC using Lee and Lyman molds. Neither mold is exactly new; been using them for 2 years; approx 100-150 bullets a week from each.

My problem is getting the bullets to fall out of the mold after I've knocked aside the top plate. 9 times out of 10 I have to bash hard 3 or 4 times on the hinge bolt with my 8" of broom handle to shake the wee perishers loose.

I'm also getting flash on the base of the bullets (ie between the mold body & the top plate). The top plates aren't loose, particularly.

What am I doing wrong? Am I pouring the lead too hot/cold? Have I ruined the molds with excessive bashing? Or have the molds simply come to the natural end of their working lives?

Also; about 5% of my bullets come out undersize, which shows up on sizing; they pass through the die unmarked. Is this because I'm casting too cold for the alloy?(I melt down scrap bullets from our range's bullet catcher, so we're talking a mixture something like; commercial cast bullet alloy 66%, pure lead from .22s 33%)

Any guidance gratefully received.

Cordially,

Lemming

[slide]

It could be a combo of all the things you mentioned. Mold temp is vital as is the alloy temp. I run my pot at around 650 degrees. This seems to work for me. I am using brass molds. The molds are preheated on a hotplate for about 30 to 45 minutes before I start casting. Get yourself a thermometer to keep an eye on your alloy temp. A guy on this forum sells them. Can't think of his name right now. There will be somebody come along who will be able to help you better than I can. Lot's of knowledge on this place and they don't mind sharing. I am just getting started myself and the suggestions I have received have been invaluable. The least banging on the molds the better.

[Czech_too]

Based upon what I have experienced and more importantly, read here, I have to say that you're cutting the sprue to early, thus the flashing. Give the lead a bit more time to 'set up' before cutting the sprue. Secondly, the reason the bullets are sticking in the mould, may be due to the temp of the mould itself. It's to hot so slow your pace some. The undersize boolits I would lay to the 'alloy' you're using. Modifying this should solve that issue.

[GP100man]

1st WELCOME to :cbpour: !!!!!!

I`d start with removing the sprue plates & cleaning the top of the molds & the plates by rubbing on 600 sand paper on glass pay particular attention around the screw holes.

Once ya get em laying flat just snug enuff to keep the plate from flopping is tite enuff.

Also so search "leementing" this will help release of boolits if any burrs are present .

Alot of times we tend to run the pot hot to make up for defenciecys in alloys ability to flow ,a little tin will help fill out . the closer the alloy is closer to pure the more it`ll shrink, temp does play a part in that but not as much as we mite think as some strive for frosty boolits .

Do you have a lead thermometer ??, since purchasing 1 I can`t imagine casting without it now .

[41 mag fan]

Pretty much slide hit it on the head.
The thermometer you can buy from NOE on the vendors sales at bottom of forum. Best person you'll ever do business with.
I run my pot at 650*-675*, while my pot is heating I use a hot plate to preheat my molds, on med/low.
Are you smoking the cavities in the molds? This could be the reason you're not getting them to fall right out.
Your sprue plate on the mold that has flashing, as you say, is it smearing on the mold or just on the bases of your casts?
If it's smearing you might try some Bull Plate on the bottom of thhe spru plate and on your mold when the cavities are filled. Put it on with a q-tip, then wipe it off with the dry end of the q-tip.
Smearing also could mean your sprue plates too hot.

From what I hear the Lyman molds of recent have been casting undersized.
Hope this helps a little.
If it's flashing on boolit bases, I have a 502 mold that does it. The Lee molds sprue plate warped on me. You might check that. I don't open my sprue plates with a broomstick ect., I use a gloved hand to prevent the sprue plates from warping or bending.

[462]

Welcome, Lemming.

Ditto on reading the Leementing sticky and using Bullplate.

Getting boolits to drop from the mould should never require more than just a gentle love tap on the handle hinge. Lapping the cavities with a mild abrasive -- Bon-Ami, Comet, toothpaste, etc. -- should fix them right up. Thoroughly clean them afterwards. It's a mighty fine sight to behold, when boolits actually jump out of mould, as soon as it's opened. I've never found the need to smoke any mould.

Don't mean to open another discussion about it, but there is a Kroil sticky, that you may find of interest.

[lemming]

Gentlemen -

First, thank you for your generous welcome and your excellent advice, which is greatly appreciated.

What's Bull Plate? I live in the UK, so US branded products aren't usually available; if you can give me some idea of what it is, I can try and find a viable substitute.

Sounds like the first thing I should do is try and remember where I put the thermometer I got with a load of other reloading stuff about 15 years ago and never bothered using...

Thanks again,

Lemming

[DLCTEX]

Sounds to me that the sprue plate is warped, causing the flashing. Do as GP 100Man suggested to level it up. I have gotten some with slightly warped plates to cast ok by loosening the screw that holds the sprue plate. And +1 on "Leementing' the moulds, the best medicine for a sticky mould going. A substitute for Bullplate lube that some have claimed good results with is Husqvarna 2 cycle oil. A slight touch on a Q-tip and applied to a hot sprue plate and the alignment pins, and maybe to the top of the mould away from the cavities (don't get it in the cavities) will do wonders. I apply and then wipe almost dry with a cotton cloth. Less is more in this case, use sparingly.

[adrians]

welcome lemming...
all of the above advice is very sound advice and should be heeded you'll be suprised at the differance a "leementing" session will do for your casting experience.
if you want real bullplate get in on one of the numerous group buys which offer molds made by Swede Nelson of NOE, they are second to non in quality i love them,, a sample of Bullsplate is supplied with each order and a nano speck of the stuff goes a long way.
just a thought.
what part of the UK do you live,,? i was born and raised in Halifax, w,yorkshire.
been residing here in the states since 1987.
have a good -un..
adrians...:evil::lovebooli:twisted:

[canyon-ghost]

I scrape the mold top and sprue plate with a razor knife sometimes to clean them. You can clean mold cavities with a pencil eraser. Kano Kroil oil makes a pretty good mold release for the cavities, too.

Good Luck,
Ron

[Bret4207]

Read the "Leementing" posts. It's basically fine tuning the moulds physical properties. The lube is a proprietary lube not currently available IIRC. 2 stroke mixing lube has been said to work nearly as well, I haven't tried it. I find lubing with a soft carpenters pencil still works for me.

[lemming]

Thanks again.

2 stroke oil I have in plenty, for the chainsaw. I'll give it a go.

Also, I've read the Leementing thread and it all sounds like excellent advice.

I checked the sprue plates for warp on a gauge plate, and they're OK. Also, I don't get flash all the time.

I found I could virtually guarantee flash-free bullets by pouring the lead from my Lee furnace not into each hole in the sprue plate but halfway between the holes... Weird, yes, but it works - except that around 10% of the bullets cast that way come out undersize. That's what started me thinking it must be a temperature issue. Must find that thermometer...

Adrians - I was born and raised in West Somerset, currently living in involuntary exile in South Somerset.

Lemming

[FirstBrit]

Thanks again.

2 stroke oil I have in plenty, for the chainsaw. I'll give it a go.

Also, I've read the Leementing thread and it all sounds like excellent advice.

I checked the sprue plates for warp on a gauge plate, and they're OK. Also, I don't get flash all the time.

I found I could virtually guarantee flash-free bullets by pouring the lead from my Lee furnace not into each hole in the sprue plate but halfway between the holes... Weird, yes, but it works - except that around 10% of the bullets cast that way come out undersize. That's what started me thinking it must be a temperature issue. Must find that thermometer...

Adrians - I was born and raised in West Somerset, currently living in involuntary exile in South Somerset.

Lemming

From what I have read sofar, I think your mould blocks are just getting too hot for this type of casting. Typical symptom is when bullets fall out freely after getting mould blocks up to temperature but as casting session progresses the bullets become "sticky" and the flashing starts occuring. Is the flashing just on the bullet base or are you also getting whiskers on the parting lines of the mould blocks?

In my opinion the ideal tension of the sprue plate is when the plate swings open gently by gravitational force when tipping the mould on its side. This needs to be checked when the mould is hot. Since if adjusted when cold the tension can either become too loose or too tight when mould blocks gets up to temperature. Depends to some degree on the material combination of mould blocks and sprue plate.

Another way to check whether it is predominantly a temperature issue is to do the following. When point is reached that bullets are "sticky" and flashing occurs is to cool the mould rapidly with a damp cloth. This is best done after filling the mould with alloy, but before breaking the sprues. The cloth should be damp but not wringing wet. Dab the cloth to the sprues - is the mould is really hot there should be a hissing sound from the evaporating water ( boiling off) Continue to dab in short 1-2 second bursts until the hissing stops. Now cut the sprue and eject the bullets and immediately refill the mould. The next bullets should now have no flashing and fall out freely. If so, then this it is an issue with temperature and the best way is to adjust the melt temperature down by 10-20°C. A bit of trial and error is needed here to determine optimum conditions.

If these tactics don't succeed it could be there is an issue with burrs on the mould cavities. Can easily occur if mould falls on a hard surface even from low heights. Or there could be some play in the locating pins of the two mould halves. And depending on how you cut the sprue especially a strong clout with a wooden hammer or similar could just give enough movement between the two mould halves that the bullet is being "pinched" and this is why they don't want to fall out easily.

Let us know how you progress.

Best regards and happy New Year to everyone,

Adrian, Germany.

P.S. Born in High Wycombe, Bucks. (U.K.) and settled in Germany since 1974.

[lemming]

Thanks for more excellent advice. I'll try that.

FirstBrit - I know High Wycombe well; round about the time you moved to Germany, I was risking life and limb trying to get my first motorbike up to 70mph going down Dashwood Hill...

Cordially,

Lemming

[Boolseye]

you can lap the mold to enlarge the cavities and/or to help the bullets drop easier. You can do the enlarging lap with valve grinding compound, then polish using comet cleaner. You can just cast a couple perfect bullets, screw a drywall screw in the base, coat bullet with compound and turn with a screwdriver. Do some searches on lapping so you don't hurt your mold, but it's not that hard. Sounds like the flashing may have to do with cutting the sprue too cold. There doesn't need to be any bashing to speak of if everything is being done properly. As for lee molds and heat–in my experience it's almost impossible to get them too hot. I dip my 2-cav molds in the melt for at least 30 seconds before casting, and have never had undersized bullets as a result of temp. On average, I cast with alloy around 750-800º, but I still get good bullets as low as 650º When the mold and/or alloy gets real hot, the bullets get frosty, not small. Happy New Year, and good casting.

[MtGun44]

VERY, VERY little lube on mold alignment features and top of mold, bottom of sprue plate.

Just touch the tip of a Q-tip to the oil, then press out all you can on the side of the neck of
the bottle. Do not get oil in the cavities.

With Bullplate, the smears of lead will go away while casting if lubed, not certain with synthetic
2 stroke oils. Find one that does not smoke and smell. Search on Bullplate Lube and you
can apparently still order via snail mail, but the guy that sells it is in the middle of nowhere
in Alaska and mail is super slow this time of year.

Bill